Membership in OPN is open to any individual, organization, company, or other entity. One becomes an OPN Member by agreeing to the OPN Membership Terms. Membership is optional and at will, and OPN Members may end their membership at any time. An OPN Member is considered active if it either attends an OPN monthly call or contacts the Chair of the Steering Committee in writing at least once per calendar year. Members who do not meet this criteria will be considered inactive as of January 1 of the following year, but may reactivate at any time. Inactive members will be marked as such on any membership lists, including the OPN website.